Abstract: An operator prompting system for a calculator of the type having stored program control for performing a limited number of pre-programmed calculations, the prompting system being adapted to guide an operator through the different programs by directly indicating the need for a data entry and the nature of such entry. In a preferred embodiment, the calculator display is of the alpha-numeric variety, and means are provided for driving the display to directly indicate upon such display the nature of the data required. The program module within the calculator may be configured to carry out complex calculations in various specialized fields, such as navigational, financial, scientific or engineering, the alpha-numeric display being used to display the numerical data as entered and the results, and also to directly call for the data required for the different programs or uses.

Abstract: An electronic computer having a limited stored program capability and adapted to perform a plurality of problems particularly useful to aircraft pilots. The unit includes an electronic calculator and a stored program controller for instructing the calculator. The programs stored in the controller cause sequential operation, including the demand for manual entry of necessary data, to calculate a desired result. The calculator includes a plurality of program selector keys operative upon the program controller for selecting the program associated with the desired result. The operating panel further includes a plurality of data entry indicators adapted to be illuminated by the controller for indicating to the operator the nature of each data entry required. The calculator is programmed to solve at least each of the following navigational and performance problems: effects of winds aloft on aircraft progress and maintenance of course, and effect of nonstandard atmospheric conditions on aircraft performance.

Abstract: A left zero fill circuit particularly suited for incorporation into non-buffered keypunch machines for providing a left zero fill capability thereto. The circuit provides a combination of registers and memory storage devices operable in an input mode to accept keypunch data, and in an output mode to punch the data onto a card in the proper locations within the field. The circuit further includes isolation means interposed in the interconnections between the keypunch machine and the left zero elements to isolate the power supplies and to allow the keypunch machine to be serviced in the normal manner, simply by switching the left zero fill circuit off.